1. Field of the Invention
The present invention relates to a digital broadcasting receiver. More particularly, the present invention relates to a method and an apparatus for selecting a channel when the digital broadcasting receiver finds channels of the same service.
2. Description of the Related Art
A digital broadcasting service can provide users with not only four or five times more vivid image quality than the conventional analog broadcasting service but also various data information in real time. Naturally, public channels and various service providers offer diverse services and the number of digital broadcasting channels is gradually increasing. With the increase in digital broadcasting channels, when a digital broadcasting receiver scans channels, a method for accurately searching for the channels within a short period of time is desired.
Meanwhile, different broadcasting channels are allocated and serviced on the regional basis. For example, channels 1 through 3 are serviced in region A and channels 4 through 8 are serviced in region B. However, while the broadcasting channels differ per region, the same broadcast can be provided in the different resigns. That is, region A broadcasts TV series in channel 1 and region B broadcasts the same TV series as in region A, in channel 8.
As such, the Local Channel Number (LCN) cannot be an identifier for uniquely identifying the broadcasting service. The same service can be identified with a service ID and an original network ID of the broadcasting service. The broadcasting service refers to the service broadcast and received in the corresponding broadcast channel. The service ID is the ID of the broadcast program and every program has its unique ID information.
FIG. 1 illustrates a diagram of same broadcasting service in an overlapping area according to the conventional art.
Referring to FIG. 1, a digital broadcasting receiver may search for channel 1 (102) of region A and channel 4 (112) of region B in the overlapping area of region A (100) and region B (110). When the service ID of the found channel 1 is the same as the service ID of the found channel 4, the digital broadcasting receiver generates a channel list by selecting either channel 1 or channel 4 of the same service and the unselected channel is not recorded in the channel list.
When channel 1 (102) and channel 4 (112) of the same service are found, the conventional method for selecting the channel is as follows.
First, as scanning broadcast channels, the digital broadcasting receiver stores a corresponding broadcast channel and signal strength information.
Next, the digital broadcasting receiver determines whether there exists the same service by checking the channel information (e.g., service ID) when the service search is completed. When detecting channels of the duplicate service, the digital broadcasting receiver generates the channel list by selecting the broadcast channel of the greater signal strength and excludes the unselected channels from the channel list. Thus, the user can select and view the corresponding broadcast service using the channel list.
FIG. 2 illustrates a diagram of same service channel selection in an overlapping area according to conventional art.
Referring to FIG. 2, channel 1, channel 2 and channel 3 of region A (200) and channel 4 of region B (210) may be found and corresponding signal strength information of each channel is stored. When channel 1 through channel 4 are found in the overlapping area, the same broadcast service is provided from channel 1 of region A (200) and channel 4 of region B (210), and the signal strength of channel 1 is greater than that of channel 4, the channel list 220 includes only channel 1, channel 2, and channel 3. Channel 4 is excluded from the channel list 220 as indicated by 206.
When the broadcast is interrupted because of the weak broadcast signal while the user is watching the broadcast in the found channel 1, the user cannot return to the previously found channel 4 of the same service and view the same broadcast (because channel 4 is excluded from the channel list). In this situation, the user has to wait until the broadcast signal is received in channel 1, or to re-search for channel 1 or channel 4 through the channel scanning.